2.Online learning can never completely replace face-to-face learning. 
Reference:Bali, S and Liu, MC（2018）Students' perceptions toward online learning and face-to-face learning courses.Journal of Physics: Conference Series Volume 1108, Mathematics, Informatics, Science and Education International Conference (MISEIC) 2018 21 July 2018, Surabaya, Indonesia
(Online)Available at :iopscience.iop.org/article/10.1088/1742-6596/1108/1/012094/meta
[Accessed on 6th August 2021]
Main ideas:The article first gives an introduction, pointing out that online learning is indeed a trend, but interactivity is a problem, and then gives a literature review, pointing out that interaction is an extremely important existence in student learning, and student satisfaction is also very important. Then the author conducted a questionnaire survey on students from several universities by means of a sample survey, and found that students generally prefer face-to-face learning. Finally, he concluded that although face-to-face learning has some advantages, it has great shortcomings such as lack of social interaction. Lack of social presence, lack of synchronization of communication.
How is this source related to the investigation:
Through research, this article gives many questions about online learning. Combined with the previous reference, it is very helpful to my second point of view:Online learning can never completely replace face-to-face learning.Because face-to-face education has some irreplaceable advantages such as social interaction

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